/Engine/Source/Runtime/Slate/Public/Framework/MultiBox/MultiBoxBuilder.h
void AddSubMenu ( const [TAttribute](API\Runtime\Core\Misc\TAttribute)< [FText](API\Runtime\Core\Internationalization\FText) > & InMenuLabel, const [TAttribute](API\Runtime\Core\Misc\TAttribute)< [FText](API\Runtime\Core\Internationalization\FText) > & InToolTip, const FNewMenuDelegate & InSubMenu, const bool bInOpenSubMenuOnClick, const [FSlateIcon](API\Runtime\SlateCore\Textures\FSlateIcon) & InIcon, const bool bInShouldCloseWindowAfterMenuSelection, [FName](API\Runtime\Core\UObject\FName) InExtensionHook )